There are a lot of pages stating that the Thinkpad T440p fingerprint sensor is not working well under Linux, but those are old and outdated. For me it worked well after figured out which packets to install:
apt-get install libfprint fprintd libfprintd
fprint-demo can also be installed to play with the sensor.
Then to enable login with the sensor in Gnome3, navigate to
- Enroll you finger.
Tested under Debian Buster Buster, fingerprint sensor model is